ISMB 250 weight and dimensions
37.3 kg/m · 25.06 lb/ft
ISMB 250 is a 250 mm deep beam with a 125 mm flange, 6.9 mm web and 12.5 mm flange thickness. It weighs 37.3 kg per metre (25.06 lb/ft). It belongs to the ISMB medium weight beam series, Indian Standard (IS 808).
ISMB 250 weight calculator
Weight of standard lengths
| Pieces | 6 m each (kg) | 12 m each (kg) |
|---|---|---|
| 1 | 223.8 | 447.6 |
| 5 | 1,119.0 | 2,238.0 |
| 10 | 2,238.0 | 4,476.0 |
| 20 | 4,476.0 | 8,952.0 |
| 50 | 11,190.0 | 22,380.0 |
Pieces per tonne
| 6 m lengths per metric tonne | 4.5 |
| 12 m lengths per metric tonne | 2.2 |
| Length per tonne | 26.8 m |
Useful for converting a tonnage order into a number of bars.
Surface area for painting
| Per metre of length | 0.964 m²/m |
| Per foot of length | 3.16 ft²/ft |
| Per tonne of steel | 25.8 m²/t |
| A 12 m length | 11.57 m² |
Outside perimeter × length, all faces, calculated from the dimensions. Use it to estimate paint, primer, fireproofing or galvanizing quantities.
Cross-section
Drawn to scale. Dimensions in mm.
Dimensions
| Depth h | 250 mm | 9.843 in |
| Flange width b | 125 mm | 4.921 in |
| Web thickness tw | 6.9 mm | 0.272 in |
| Flange thickness tf | 12.5 mm | 0.492 in |
| Root radius r | 13 mm | 0.512 in |
| Toe radius r2 | 6.5 mm | 0.256 in |
| Flange slope (deg) | 98° | |
| Mass | 37.3 kg/m | 25.06 lb/ft |
Section properties
| Property | Value | Unit |
|---|---|---|
| Area | 47.50 | cm² |
| Moment of inertia Ix | 5,130 | cm⁴ |
| Moment of inertia Iy | 334 | cm⁴ |
| Elastic modulus Zx | 410 | cm³ |
| Elastic modulus Zy | 53.50 | cm³ |
| Plastic modulus Zpx | 465 | cm³ |
| Plastic modulus Zpy | 89.70 | cm³ |
| Radius of gyration rx | 10.30 | cm |
| Radius of gyration ry | 2.65 | cm |
| Torsion constant J | 25.50 | cm⁴ |
Equivalent sections in other standards
The closest sections by depth and weight. They are not direct substitutes: check bending, buckling and connection details before swapping one for another.
ISMB 250 and its closest equivalents, drawn over each other at the same scale.
| Section | Standard | Depth (mm) | kg/m | Weight vs ISMB 250 |
|---|---|---|---|---|
| ISMB 250 | IS | 250 | 37.3 | — |
| IPE 270 | EN | 270 | 36.07 | -3.3% |
| IPE 240 | EN | 240 | 30.71 | -17.7% |
| S10x25.4 | AISC | 254 | 37.80 | +1.3% |
| W10x26 | AISC | 262 | 38.50 | +3.2% |
ISMB series weights
Next lighter: ISMB 225 (31.15 kg/m). Next heavier: ISMB 300 (46.02 kg/m).
Stiffness and strength per kilogram
The elastic section modulus Zx governs bending strength. Dividing it by the weight shows how efficiently each size uses its steel: higher is better when weight is the cost driver.
| Section | kg/m | Ix (cm⁴) | Zx (cm³) | Zx per kg/m |
|---|---|---|---|---|
| ISMB 175 | 19.50 | 1,260 | 144.0 | 7.38 |
| ISMB 200 | 24.17 | 2,110 | 211.0 | 8.73 |
| ISMB 225 | 31.15 | 3,440 | 306.0 | 9.82 |
| ISMB 250 | 37.30 | 5,130 | 410.0 | 10.99 |
| ISMB 300 | 46.02 | 8,990 | 599.0 | 13.02 |
| ISMB 350 | 52.33 | 13,600 | 779.0 | 14.89 |
| ISMB 400 | 61.55 | 20,400 | 1,020.0 | 16.57 |
Full table: ISMB weight chart (PDF).
How the weight is calculated
Mass per metre = cross-sectional area × density of steel = 47.50 cm² × 0.785 kg/(cm²·m) = 37.29 kg/m.
Rolled sections are made to a nominal mass, and the actual mass can differ by a few percent within the tolerances of IS 1852. For purchasing, invoicing by weight or checking deliveries, use the producer's stated mass.
Typical uses
Beams of this shape are used as floor and roof beams, lintels, crane girders and frame members, where bending about the strong axis governs.
Frequently asked questions
What is the weight of ISMB 250 per metre?
ISMB 250 weighs 37.3 kg/m, which is 25.06 lb/ft.
How much does a 6 m or 12 m length of ISMB 250 weigh?
A 6 m length weighs about 223.8 kg and a 12 m length about 447.6 kg.
What is the equivalent of ISMB 250 in other standards?
By depth and weight the closest match is IPE 270 (36.07 kg/m, 270 mm deep). Check section properties before substituting one for the other.
Source: IS 808:2021; earlier values from IS 808:1989 and SP 6(1):1964. Values are nominal; verify with the producer before ordering.